Method for producing a continuous metal strip which is provided with slotted openings, metal strip, and molded body

Abstract

The invention relates to a method for producing a continuous metal strip (16) which is provided with slotted openings (22), having the following steps: a) providing a strip end (24) of a metal strip (16), which is unwound from a coil, and a strip start (26) of a metal strip (16), which is unwound from another coil; b) introducing a contour (28) into the strip end (24) and a mating contour (30), which corresponds to the contour (28), into the strip start (26); c) bringing the contour (28) and the mating contour (30) together such that the contour (28) and the mating contour (30) engage into each other in a form-fitting manner along a connection line (38); d) welding together the strip end (24) and the strip start (26) along the connection line (38); and e) introducing slots (17) into the metal strip (16) by means of a rotative cutting process. The invention additionally relates to a metal strip (16) produced using such a method and to a molded body which has at least one such metal strip (16) and a casing made of a molding compound that can be injection molded.

Description

[0001] Method for producing an endless metal strip provided with slotted openings, a metal strip and a shaped body

[0002] The invention relates to a method for producing an endless metal strip provided with slotted openings. Furthermore, the invention relates to a metal strip produced by such a method and a molded body comprising such a metal strip.

[0003] Metal strips of the type mentioned above are used, for example, to reinforce a molded body made of a moldable compound, such as a sealing strip or an edge protection strip made of an elastomeric material. Such a sealing strip or edge protection strip is used for openings in a vehicle, such as a window opening, a door opening, or a tailgate opening.

[0004] To secure the sealing or edge protection strip, the opening is provided with a flange surrounding the opening, onto which the sealing or edge protection strip is clipped or clamped. For this purpose, the metal strip is formed into a V-shaped or U-shaped profile.

[0005] To produce a sealing or edge protection strip, the metal strip, formed into a V-shaped or U-shaped profile, is coated with an injection-moldable molding compound, such as a plastic and / or an elastomer, in an extrusion process. To enable the injection-moldable molding compound to adhere to the metal strip, the metal strip is provided with slits. The slits are punched into the metal strip in a continuous manufacturing process and then expanded into openings by subsequent stretching, for example, by rolling.

[0006] In addition, metal strips of the type mentioned above can also be used as filters, sieves, or gratings. For a continuous production process of a metal strip with slotted openings, the end of a metal strip unwound from one coil is connected to the beginning of a metal strip from another coil. For this purpose, the end and beginning of the strip are welded together.

[0007] DE 20 2012 012 894 U1 discloses a device for quickly connecting a strip end of a metal strip in a processing process, unwound from a coil, to the strip beginning unwound from a next coil, thereby creating a location-specific but arbitrarily contoured cutting or connecting line. The device comprises a clamping device having a first clamping tool and a second clamping tool that is movable relative to the first clamping tool, a device for adjusting the location of the cutting line to be created at the strip end depending on the processing of the metal strip, at least one cutting device for creating the cutting line from the strip end and strip beginning, and a welding device for connecting the contoured strip end to the contoured strip beginning along the created connecting line.The connecting or welding line is adapted to the contours of the workpieces to be punched out, so that the connecting or welding line is always placed in the area of ​​the waste piece between the workpieces or punched parts, which reliably prevents the processing tool from coming into contact with the welding line.

[0008] The present invention is based on the object of creating a method, a metal strip and a shaped body which enable an improved connection of two metal strips for a continuous manufacturing process.

[0009] To achieve the object, a method having the features of claim 1, a metal strip having the features of claim 10 and a shaped body having the features of claim 11 are provided.

[0010] Advantageous embodiments of the method are the subject of the dependent claims. According to one aspect of the invention, a method for producing an endless metal strip provided with slotted openings is proposed. In the method, in a first step, a strip end of a metal strip unwound from one coil and a strip beginning of a different metal strip unwound from another coil are provided. In a second step, a contour is introduced into the strip end and a counter-contour corresponding to the contour is introduced into the strip beginning. In a third step, the contour and the counter-contour are brought together so that the contour and the counter-contour interlock along a connecting line. In a fourth step, the strip end and the strip beginning are welded together along the connecting line. In a fifth step, slots are introduced into the metal strip by rotary cutting.

[0011] The process is characterized by the joining or welding line resulting from the contour and the counter-contour. The joining line ensures a constant heat-affected zone distributed across the metal strip, thus enabling continuous transitions of the mechanical properties in the longitudinal and transverse directions across the metal strip. Furthermore, the joining line resulting from the contour and counter-contour allows for an extension of the weld seam. Furthermore, the joining line features continuous geometric transitions and thus self-locking properties. Finally, the joining line is independent of the cutting or slot geometry.

[0012] The metal strip may be made of steel or aluminum, in particular an aluminum alloy.

[0013] Advantageously, the connecting line for welding the beginning of the strip to the end of the strip defines the welding line.

[0014] In rotary cutting, which can also be referred to as a roll cutting process or rotary cutting process, slits are cut into the metal strip using a rotating cutting wheel. In an advantageous embodiment, the contour and the counter-contour have at least one rounded section. This at least one rounded section avoids areas at 0° and 90° to the longitudinal direction of the strip. Furthermore, the weld seam is located in at least one cut, so that the original material is retained in this cut. This reduces the heat-affected zone or heat transfer zone.

[0015] In an advantageous embodiment, the contour and the counter-contour are contoured such that at least two slots intersect the connecting line. Thus, the connecting line is independent of the cutting or slot geometry. Furthermore, the original material is retained in each cut, thus reducing the heat-affected zone or heat transfer zones.

[0016] In an advantageous embodiment, the connecting line is arranged symmetrically or asymmetrically to the center line of the metal strip and / or the slots are arranged symmetrically or asymmetrically to the center line of the metal strip.

[0017] In an advantageous embodiment, the contour has at least one extension protruding from the band end and / or at least one recess made in the band end, which engages in a form-fitting manner in the at least one corresponding recess and / or in the at least one corresponding extension of the mating contour. Advantageously, the contour has a puzzle shape and the mating contour has a corresponding puzzle-shaped recess. As a result, the connecting line has a geometry with self-locking properties. Advantageously, the extension has a round head and the corresponding mating contour has a round recess similar to a puzzle piece. Furthermore advantageously, the contour has two or more extensions protruding from the band end, in particular round, head-shaped extensions, which engage in a form-fitting manner in two or more corresponding recesses, in particular corresponding round recesses.

[0018] In an advantageous embodiment, the contour and counter-contour are introduced by cutting and / or punching the strip end and the strip beginning. Cutting and / or punching enables the contour to be introduced into the strip end and the counter-contour into the strip beginning in a simple, quick, and cost-effective manner.

[0019] In an advantageous embodiment, the contour and the counter-contour are introduced into the strip end and the strip beginning by laser cutting. Laser cutting allows for a precise contour to be introduced into the strip end and a corresponding counter-contour to be introduced into the strip beginning.

[0020] In an advantageous embodiment, the strip end and strip beginning are welded together along the connecting line by laser welding. During laser welding, the heat input into the metal strip and thus the heat-affected zone created to the left and right of the weld seam are evenly distributed. As a result, the metal strip exhibits continuous transitions in its mechanical properties in the longitudinal and transverse directions along the connecting line or welding line.

[0021] It is advantageous to use the same laser for cutting and welding.

[0022] In an advantageous embodiment, the slits are widened into openings by pulling and / or stretching the metal strip. During the drawing or stretching process, the metal strip is pulled lengthwise along the strip's length, and during the stretching process, the metal strip is preferably rolled lengthwise along the strip's length by means of rollers. During both the drawing and stretching processes, the slits are widened into openings or perforations.

[0023] According to a further aspect of the invention, a metal strip is proposed which is produced by means of a method according to the invention.

[0024] The metal strip can be an insert for a sealing strip, a decorative strip or an edge protection strip, a filter, a sieve or a grid.

[0025] The metal strip may have a plurality of edge slots extending inward from the edges of the metal strip transversely to the strip's longitudinal direction, and central slots arranged between the edge slots. Both the edge slots and the central slots may be widened to form openings or perforations.

[0026] The edge and center slots can be created in the metal strip by rotary cutting, which can also be referred to as rotary cutting or roll cutting, using a rotating cutting wheel (not shown). Advantageously, the metal strip is stretched after slitting by being pulled lengthwise along the strip's length, or by rolling, thereby expanding the edge and center slots to form openings.

[0027] In an advantageous embodiment, the edge slots and / or the center slots taper inward, and / or are wedge-shaped and / or rounded. Advantageously, the edge slots are open on the outside of the band, meaning that the edge slots do not have a closed border at the edges of the base body. The center slots advantageously have a closed border, meaning that the center slots have a closed contour. The closed contour can be diamond-shaped, hexagonal, and / or slot-shaped.

[0028] According to a further aspect of the invention, a shaped body is proposed which comprises at least one metal strip according to the invention and a covering made of an injection-moldable molding compound.

[0029] The molded body can be a sealing strip, a decorative strip, or an edge protection strip, particularly for a vehicle, into which the metal strip for reinforcing the molded body is embedded. The injection-moldable molding compound can be a plastic and / or an elastomeric material.

[0030] The formed body can have a sealing lip and a mounting slot for mounting the formed body onto a flange surrounding an opening. Advantageously, the metal strip is formed into a V-shaped or U-shaped profile and embedded in the receiving slot. Advantageously, the metal strip bent into a V-shaped or U-shaped profile always retains its original material when subjected to a load perpendicular to the weld line due to the connecting or welding line resulting from the contour and the counter-contour. A formed body, a metal strip, a method, and other features and advantages are explained in more detail below using exemplary embodiments schematically illustrated in the figures. Herein:

[0031] Fig. 1 is a perspective view of a molded body with an endless metal strip provided with slotted openings according to a first embodiment and a covering made of an injection-moldable molding compound;

[0032] Fig. 2 is a plan view of the endless metal strip with a connecting line according to a first embodiment, wherein a strip end of a metal strip unwound from one coil and a strip beginning of a metal strip unwound from another coil are connected along the connecting line to form the endless metal strip;

[0033] Fig. 3 a plan view of the strip end of the metal strip with one contour and the strip beginning of the other metal strip with a counter contour;

[0034] Fig. 4 is a schematic representation of the process steps for producing the endless metal strip shown in Fig. 2;

[0035] Fig. 5 is a plan view of an endless metal belt according to a second embodiment with a connecting line according to the first embodiment;

[0036] Fig. 6 is a plan view of an endless metal belt according to a third embodiment with a connecting line according to a second embodiment;

[0037] Fig. 7 is a plan view of the endless metal strip with a connecting line according to a third embodiment; and

[0038] Fig. 8 is a plan view of the endless metal strip with a connecting line according to a fourth embodiment. Fig. 1 shows a molded body 10, which in this case serves as a seal 12 for sealing an opening (not shown), such as a window opening, a door opening, or a tailgate opening, of a vehicle (not shown).

[0039] The molded body 10 has a casing 14 made of an injection-moldable molding compound, for example an elastomeric material, and an endless metal band 16 which is embedded in the casing 14 and surrounded by the same.

[0040] The metal strip 16 is made of steel or aluminum, in particular an aluminum alloy, and has a plurality of slots 17. The slots 17 include edge slots 18, which extend inward from edges 20 of the metal strip 16 transversely to the strip's longitudinal direction LB, and center slots 20 arranged between the edge slots 18. As can be seen in Fig. 2, the edge slots 18 and the center slots 20 are arranged symmetrically to the center line LM of the metal strip 16.

[0041] As can be seen particularly in Figures 1 and 2, both the edge slots 18 and the central slots 20 are widened to form openings 22 or breakthroughs.

[0042] The edge slits 18 and the center slits 20 are introduced into the metal strip 16 by rotary cutting, which can also be referred to as rotary cutting or roll cutting, using a rotating cutting wheel (not shown). After slitting, the metal strip 16 is drawn or stretched by being pulled elongated in the strip's longitudinal direction LB, or the metal strip 16 is stretched by rolling, whereby the edge slits 18 and the center slits 20 are widened to form the openings 22.

[0043] To enable continuous processing of the metal strip 16, in particular to enable continuous slitting and subsequent toeing or stretching of the metal strip 16, as shown in Fig. 3, a strip end 24 of the metal strip 16 unwound from one coil is connected to a strip beginning 26 of the metal strip 16 of the next coil. For this purpose, as shown in Fig.

[0044] 3, a contour 28 is introduced into the strip end 24 and a counter-contour 30 corresponding to the contour 28 is introduced into the strip beginning 26 by cutting, in particular by laser cutting, or by punching. The contour 28 and the counter-contour 30 have at least one rounded section 32; in particular, the contour 28 has a rounded extension 34 protruding from the strip end 24 and the counter-contour 30 has a corresponding rounded recess 36 introduced into the strip beginning 26. As can be seen in Fig. 3, the contour 28 and the corresponding counter-contour 30 are puzzle-shaped in the present case.

[0045] The contour 28 and the counter-contour 30 are brought together by inserting the contour 28, in particular the extension 34, into the counter-contour 30, in particular into the recess 36. As can be seen in Fig. 3, the contour 28 and the counter-contour 30 engage with each other in a form-fitting manner along a connecting line 38, which in this case is arranged symmetrically to the center line LM of the metal strip 16. In order to firmly connect the strip end 24 to the strip beginning 26, the strip end 24 and the strip beginning 26 are welded together along the connecting line 38, as can be seen in Fig. 2.

[0046] After welding, the edge slots 18 and the center slots 20 are introduced into the metal strip 16, as previously described. As can be seen in particular in Fig. 4, the contour 28 and the counter-contour 30 are contoured such that both the edge slots 18 and the center slots 20 intersect, in particular sever, the connecting line 38 and the welding line, respectively.

[0047] In the following, a possible manufacturing method of the endless metal strip 16 is described with reference to Fig. 4.

[0048] In a first step S1, the strip end 24 of the metal strip 16 unwound from a coil (not shown) and the strip beginning 26 of the metal strip 16 unwound from another coil (not shown) are provided.

[0049] In a second step S2, the contour 28 is introduced into the strip end 24, and the counter-contour 30 corresponding to the contour 28 is introduced into the strip beginning 26 by laser cutting. In a third step S3, the contour 28 is inserted into the counter-contour 30 so that the contour 28 and the counter-contour 30 interlock along the connecting line 38.

[0050] In a fourth step S4, the strip end 24 and the strip beginning 26 are welded together along the connecting line 38 by laser welding.

[0051] In a fifth step S5, the edge slots 18 and the center slots 20 are introduced into the metal strip 16 by rotary cutting.

[0052] In a sixth step S6, the metal strip 16 is drawn into length by stretching or rolling in the strip longitudinal direction LB in order to widen the edge slots 18 and the center slots 20 to the openings 22.

[0053] Further embodiments for the contour 28 and the counter contour 30 are described below, the same reference numerals being used for identical or functionally identical parts.

[0054] Fig. 5 shows a second embodiment of a metal strip 16 that differs from the first embodiment in the slot geometry and the symmetry of the slots 17 relative to the center line LM of the metal strip 16. As can be seen in Fig. 5, the slots 17 are arranged asymmetrically relative to the center line LM of the metal strip 16.

[0055] The strip end 24 and the strip beginning 26 are connected to each other via a connecting line 38 or welding line arranged symmetrically to the center line LM of the metal strip 16.

[0056] Fig. 6 shows a third embodiment of a metal strip 16, which differs from the second embodiment in the symmetry of the slots 17 relative to the center line LM of the metal strip 16. As can be seen in Fig. 6, the slots 17 are arranged symmetrically relative to the center line LM of the metal strip 16.

[0057] In addition, Fig. 6 shows a second embodiment of the connecting line 38 or welding line. As can be seen in Fig. 6, the second embodiment differs from the first embodiment shown in Figs. 2 and 5 in that the connecting line 38 and thus the contour 28, in particular the extension 34, and the counter-contour 30, in particular the recess 36, are arranged asymmetrically to the center line LM of the metal strip 16.

[0058] Fig. 7 shows a third embodiment for the connecting line 38 or welding line, which differs from the other two embodiments in that the contour 28 has an extension 34 and a recess 36 which point in opposite directions in the strip longitudinal direction LB, as well as two counter contours 30 which have a recess 36 corresponding to the extension 34 of the contour 28 and an extension 34 corresponding to the recess 36 of the contour 28, which also point in opposite directions in the strip longitudinal direction LB.

[0059] In Fig. 8, a fourth embodiment for the connecting line 38 or welding line is shown, which differs from the other embodiments in that the contour 28 has two extensions 34 and a recess 36 arranged therebetween and that the counter contour 30 has two corresponding recesses 336 and a projection 34 arranged therebetween.

[0060] As can be seen in Fig. 8, the two extensions 34 of the contour 28 point in the same direction in the strip longitudinal direction LB, and the recess 36 of the contour 28 arranged therebetween points in the opposite direction in the strip longitudinal direction LB. Correspondingly, the two recesses 36 of the counter-contour 30 point in the same direction in the strip longitudinal direction LB, and the extension 34 of the counter-contour 30 arranged therebetween points in the opposite direction in the strip longitudinal direction LB.

[0061] The metal strip 16 and the process are characterized by the connecting line 38 or welding line resulting from the contour 28 and the counter-contour 30. The connecting line 38 ensures a constant heat-affected zone distributed across the metal strip 16 and thus enables continuous transitions of the mechanical properties in the longitudinal and transverse directions across the metal strip 16. Furthermore, the connecting line 38 resulting from the contour 28 and counter-contour 30 creates an extension of the weld seam. In addition, the connecting line 38 exhibits continuous geometric transitions and thus self-locking properties. Furthermore, the connecting line 38 is independent of the cutting or slot geometry.

[0062] List of reference symbols

[0063] 10 molded bodies

[0064] 12 Seal

[0065] 14 Wrapping

[0066] 16 metal band

[0067] 17 Slot

[0068] 18 edge slot

[0069] 20 center slot

[0070] 22 Opening

[0071] 24 End of tape

[0072] 26 beginning of volume

[0073] 28 Contour

[0074] 30 Counter contour

[0075] 32 rounded section

[0076] 34 Extension

[0077] 36 recess

[0078] 38 connecting line

[0079] LB longitudinal direction of the strip

[0080] LM midline

[0081] S1 first step

[0082] S2 second step

[0083] S3 third step

[0084] S4 fourth step

[0085] S5 fifth step

[0086] S6 sixth step

Claims

Claims 1. A method for producing an endless metal strip (16) provided with slotted openings (22), comprising the following steps: a. providing a strip end (24) of a metal strip (16) unwound from one coil and a strip beginning (26) of a metal strip (16) unwound from another coil; b. introducing a contour (28) into the strip end (24) and a counter-contour (30) corresponding to the contour (28) into the strip beginning (26); c. bringing the contour (28) and the counter-contour (30) together so that the contour (28) and the counter-contour (30) engage one another in a form-fitting manner along a connecting line (38); d. welding the strip end (24) to the strip beginning (26) along the connecting line (38); and e. Cutting slots (17) into the metal strip (16) by rotary cutting.

2. Method according to claim 1, characterized in that the contour (28) and the counter contour (30) have at least one rounded section (32).

3. Method according to claim 1 or 2, characterized in that the contour (28) and the counter-contour (30) are contoured such that at least two slots intersect the connecting line (38).

4. Method according to one of the preceding claims, characterized in that the connecting line (38) is arranged symmetrically or asymmetrically to the center line (LM) of the metal strip (16) and / or that the Slots are arranged symmetrically or asymmetrically to the center line (LM) of the metal strip (16).

5. Method according to one of the preceding claims, characterized in that the contour (28) has at least one extension (34) projecting from the band end (24) and / or at least one recess (36) made in the band end (24), which engages in a form-fitting manner in the at least one corresponding recess (36) and / or in the at least one corresponding extension (34) of the counter-contour (30).

6. Method according to one of the preceding claims, characterized in that in step b) the contour (28) and counter-contour (30) are introduced by cutting and / or punching the strip end (24) and the strip beginning (26).

7. Method according to claim 6, characterized in that the contour (28) and the counter-contour (30) are introduced into the strip end (24) and into the strip beginning (26) by laser cutting.

8. Method according to one of the preceding claims, characterized in that in step d) the strip end (24) and the strip beginning (26) are welded together along the connecting line (38) by laser welding.

9. Method according to one of the preceding claims, characterized in that after step e) the slots (17) are widened to form openings (22) by toes and / or stretching of the metal strip (16).

10. Metal strip (16) produced by a method according to one of claims 1 to 9.

11. A molded body (10) comprising at least one metal strip (16) according to claim 10 and a casing (14) made of an injection-moldable molding compound.

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